Dentists are concerned that the selling cans of sugary drinks to pupils will undermine the work they have been doing to teach children how to look after their teeth and gums.
The British Dental Health Foundation (BDHF) also says that with obesity becoming a major problem in the UK, allowing children to buy fizzy drinks during school-time will not help matters.
Many schools at the moment have limited funds. Vending machines selling pop and other unhealthy food products help to raise that much needed extra income.
However, dentists and other medical professionals believe this a very misguided approach, and will only fuel major health problems which will cost the country as well as individuals in the longer term.
Interestingly, although some schools have taken a responsible view and posed a ban on sugary drinks during lunchtime, this has caused a backlash from some parents.
The government is also reluctant to intervene. The health minister recently suggested that head teachers are acting responsibly.
Chief executive of the BDHF, Dr. Nigel Carter told reporters that fizzy drinks are one of the major causes of dental health problems in children.
He pointed out that one in 4 children starting school will do so with tooth decay already.
Although canned pop is banned in all local authority controlled schools, the present government have been encouraging schools to opt out, and manage their own affairs as they see fit.
As a result, academies and the controversial free schools set up after 2010 are not obliged to ban such products, although the government is said to be re-writing the law to encourage them to do so.
Whether it works or not is another matter. The government have ruled out legislation banning outright the sale of fizzy drinks and other sugary foods and beverages.